Upon arrival customer stated that she just moved into home and this was the third day and what stopped working. After inspection of system found that unit had a failed gas valve. Along with a failed gas valve unit had a numerous amount of issues. The crawl space was encapsulated with a 80% furnace still under the house. The flue pipe goes into the chimney where it’s very rusted and holes and exit venting flu gas back into crawl space. The inducer draft motor housing is rusted, inside heat exchanger is compromised and rusted. Blower wheel is very dirty, blower capacitor is bad. Duct system is in very bad shape. Ac evaporator coil is very rusted, outdoor unit very aged. Advised customer due to flue pipe not being up to code, the flu leakage coming into crawl space, age and condition of system, and unit needing to be a 90% system in an encapsulated crawl space I can not give repair estimate for system. Recommended speaking with our install super about updating system and duct work, custom